<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div class="box">
        <label>
            <img src="" id="eye">
        </label>
        <input type="password" id="pwd">
    </div>
    <script>
        var eye = document.getElementById('eye')
        var pwd = document.getElementById('pwd')
        eye.onclick = function () {
            if (pwd.type == 'password') {
                pwd.type = 'text'
                eye.src = ''
            } else {
                pwd.type = 'password'
                eye.src = ''
            }
        }
    </script>
</body>
</html>